Andy Coulson, described as Mr Cameron's ex-spin doctor, has been much in the news of late, advising the Conservatives on how to deal with the UKIP threat.

This is the man, of course, who is due to stand trial on phone-hacking related charges, and is perhaps the last man on earth to complain about the political sleaze pervading UKIP. Nor indeed, as former Sun journalist and News of the World editor, inhabiting the lower end of the journalistic trade, does he have any real claim to being a political strategist of any note.

If he did, Coulson would without doubt be advising his former master that the one way guaranteed to destroy UKIP would be for him to invoke Article 50 and to notify the European Council that the UK intended to leave the European Union.

By then seeking EFTA/EEA membership – otherwise known as the "Norway Option" - Mr Cameron could thereby protect our membership of the Single Market, and at the same time negotiate a lasting relationship with the remaining member states – precisely that which he claims to want as his objective.

A brighter, more perspicacious Mr Coulson might also tell David Cameron that UKIP's greatest weakness is Nigel Farage, not for what he is currently described as, the inauthentic "Mr Mirage", but for his craven lack of leadership, exemplified by his continued sitting on the fence over Article 50. If Cameron himself wasn't sitting on the fence, this would be the strongest weapon in his armoury.

Farage's weakness in the leadership department continues to be at its most evident with his tolerance of the extraordinary intervention by Gerald Batten on Article 50.

Here we have an MEP actively promoting a policy line on a contentious issue, acting in many ways as the cheerleader of a particular caucus within the party, and all we get from Farage is silence, leaving the initiative to Batten. Could we imagine any other party leader leaving the floor to one of his subordinates, refusing to state the party's position on a key policy issue?

Probably, we can give examples, but in all cases, they would support accusations of weakness and indecision, and it is no different with Farage. This is ultimately a display of weakness.

It is not as if Batten, a salesman for British Telecom for 28 years, has any track record on legal issues yet, suddenly he is reinventing himself as a constitutional lawyer, publishing an ex cathredadissertation without the slightest benefit of citations from academic or legal authorities. Unlike the rest of us, Mr Batten, salesman extraordinaire, is a sufficient authority in his own cause. The rules of scholarship do not apply to him.

Thus does this revered constitutional expert set out, as a matter of uncontested truth (in his opinion), the "legal basis for unconditional withdrawal". According to the mighty Batten, the United Kingdom is a "dualist jurisdiction". This means that our international treaties are, as such, completely separate matter from our law.

International treaties, he earnestly tells us – without, of course, the benefit of any external authority - do not become part of our law unless expressly "incorporated" by an Act of Parliament. Thus, says the great sage: "It follows that, whatever a treaty may say about withdrawal, Parliament can always remove that treaty from the body of our domestic law simply by repealing its earlier Act. From that moment, the treaty becomes a purely foreign affair affecting nobody except diplomats".

As to the assertion that the UK is a "dualist jurisdiction", for a country that does not have a codified constitution, some might think that is something of an over-simplification. Given the choice between dualist and a monist system, most jurisdictions end up being messy hybrids, as this paper seems to indicate. Except in Mr Batten's world, rarely do we enjoy clean-cut black and whites.

It might be more correct to say, therefore, that we have adopted something of a hybrid system, where most treaties (with the exception of European Union treaties) go through a semi-automatic process of parliamentary ratification, having been signed for the most part under Crown prerogative.

No great legal authority is required to confirm this, other than that of Parliament itself. It has codified the procedure, once set out in the Ponsonby Rule, in the Constitutional Reform and Governance Act (CRaG Act) 2010. This came into force on 11 November 2010.

Treaties, as is made clear by the Act and the explanatory note, are normally ratified by Parliament under the CraG procedures, but may be ratified under Crown prerogative. In any event, they can (and mostly do) come into force without the benefit of a specific Act of Parliament. Mr Batten, the great constitutional lawyer, seems to have got it wrong.

Batten nevertheless suggests that because treaties are brought into force by Acts of Parliament, they can be removed from the body of our domestic law simply by repealing these Acts. Since, in general terms, such Acts do not exist, this cannot be true, except that EU treaties are dealt with differently. They are ratified and given force by the European Communities Act 1972, as amended. This does mean that the legal force of EU treaties can be removed by repeal of the ECA.

That is precisely what Mr Batten wants us to do, and indeed "we" (as in Parliament, prompted by government) can do that. But here, there is confusion between what we can do – in theory – and what any government could or should do, or would want to do (with or without the aid of Parliament).

Unfortunately for Mr Batten, the UK subscribes to one central tenet, which it applies rigorously to international law: pacta sunt servanda – loosely, "agreements must be obeyed". Testament to this is writ through hundreds of Hansard references, such as this one from Denis MacShane, then Minister of Europe.

Much as Mr Batten would like to ignore it, conformity with treaties is a dominant principle in Britain's treatment of international law. It is part of what is known as supplementary law, which includes general principles of law and rules of public international law.

However, Mr Batten seems quite happy with the Vienna Convention on the Law of Treaties, so he would presumably accept Article 26 which states "[e]very treaty in force is binding upon the parties to it and must be performed by them in good faith".

If he had a little bit more experience – and perhaps honesty – Batten might have referred to pacta sunt sevanda but then offered the obvious counter: clausula rebus sic stantibus. Such a great constitutional lawyer would have no difficulty asserting that treaties are binding "so long as things stand as they are".

Instead, however, Batten seeks to assert that Britain's membership of the European Economic Community in 1972 was unlawful under the English constitution. What he fails to do, though, is understand the difference between assertion and fact. Anyone may assert, but that does not make it fact. Mr Batten does not seem to know this.

Thus does he argue that EEC membership (or accession to the EC treaties) "created another legislature over the Queen in Parliament and purports the supremacy of EU legislation; it purports to bind future Parliaments contrary to a
fundamental principle of the English constitution". Further, he asserts that, "it establishes an alternative government by unelected foreign bodies without the consent of the British people".

The problem here, as we all know, is that there is no codified constitution, and no bar to Parliament modifying any part of the constitution, such that it is. Batten cannot have it both ways. He wants the British Parliament to be sovereign. Therefore, it must have the sovereign power to amend the constitution by agreeing to the EC (and now EU) treaties. These are now part of our constitution, because Parliament made them so.

Thus, at any level, our EU membership cannot be unlawful. The people who define the law (and our constitution) have declared it lawful.

On the basis of his series of assertions, though, Batten further asserts that Article 50 does not bind us in international law. Under the Vienna Convention, he says, no provision of an international treaty can override a fundamental constitutional principle of national law.

Here, most legal scholars would actually cite the relevant Article of the Vienna Convention, and at least doff their cap to the many arguments on this issue, recognising that they are not the only toilers in this field. But such a great authority as Mr Batten clearly has no need of trivial conventions. We can see, though, that he is skirting over Art. 27, which says: "A party may not invoke the provisions of its internal law as justification for its failure to perform a treaty" and goes straight to Art 46.

Despite that, Art 46 is not quite as Mr Batten would have it. It actually says that "a State may not invoke the fact that its consent to be bound by a treaty has been expressed in violation of a provision of its internal law regarding competence to conclude treaties as invalidating its consent unless that violation was manifest and concerned a rule of its internal law of fundamental importance".

Then we come to the definition of "manifest". A violation is manifest "if it would be objectively evident to any State conducting itself in the matter in accordance with normal practice and in good faith".

What also matters here is the reference to the State. Judging violations is for the State concerned – not Mr Batten, however passionate a BT salesman of 28-years standing may feel about such things. It is the state that matters. As this paper asserts, international law is built on the foundation of state consent. A state's legal obligations are overwhelmingly - some would say exclusively - based on its consent to be bound.

In this case, the State of the United Kingdom, endorsed by Parliament, accepts the validity of the treaties and considers itself bound by the precept pacta sunt sevanda, as embodied in Article 26 of the Vienna Convention. On that basis, with Parliament having reaffirmed the treaties many times, right up to ratifying Lisbon, one could say that even if there had been any doubt, Art 45(b) applies.

Mr Batten might not like this but, unless he can get a Supreme Court panel to agree that his ideas should prevail, he is on his own. So far as I am aware, he has not yet convinced any learned judges of the erudition and rectitude of his arguments. Nor even has he produced any learned papers on the subject, of a standard that would pass muster in any peer reviewed journal. Therefore, we must assume that the EU treaties, for all practical purposes, are lawful.

Nevertheless, given an opportunity, I am sure Mr Batten that, could raise an argument based on clausula rebus sic stantibus, as a prelude to invoking Art 62 of the Vienna Convention. There is a slight problem here, though, in that this is effectively invalidated by Art 45(b). And even if it was not, the doctrine of lex specialis would apply - or, as Mr Batten would be quick to tell us, lex specialis derogat legi generali.

That, necessarily, brings us right back to Art 50 of the EU treaty. To leave the EU, we have to invoke the Article. There is no other sensible option. We have to work with what is, not with what we would like things to be.

In passing, if Mr Batten wanted to know what a real scholarly article looked like, he might read this, which has some relevance here. As for his "paper", it is barrack-room lawyer stuff, a wonderful exemplar of the dictum: a little (in this case very little) knowledge is a dangerous thing.

This makes it all the more remarkable that Farage does not respond to it. It really cannot be in his interest or the interest of his party - much less the interests of the anti-EU movement as a whole - that such ill-informed material is allowed to make the running. If he has any, Farage should assert his authority and consign Batten to the margins where he belongs.